U.S. Pat. No. 4,468,400 describes tricyclic imidazo[1,2-a]pyridines having various ring systems fused onto the imidazopyridine parent structure, which should be suitable for the treatment of peptic ulcer disorders. The International Patent Application WO 95/27714 describes 8,9-dihydropyrano[2,3-c]imidazo[1,2-a]pyridines having gastric acid secretion-inhibiting properties.